[noun] a particular environment or walk of life; "his social sphere is limited"; "it was a closed area of employment"; "he's out of my orbit" Synonyms: domain, area, orbit, field, arena
[noun] any spherically shaped artifact
[noun] the geographical area in which one nation is very influential Synonyms: of influence
[noun] a particular aspect of life or activity; "he was helpless in an important sector of his life" Synonyms: sector
[noun] a solid figure bounded by a spherical surface (including the space it encloses)
[noun] a three-dimensional closed surface such that every point on the surface is equidistant from the center
